This section provides background information related to the present disclosure, which is not necessarily prior art.
Flapper doors are used on cooling fan shrouds to open the shroud, thereby improving airflow through a radiator during high speed conditions and when the fan is not in use. Existing hard plastic flapper doors are suitable for their intended use, but are subject to improvement. For example, existing flapper doors often produce undesirable levels of noise. The present teachings advantageously provide flapper doors that generate less noise as compared to current flapper doors, as explained herein. The present teachings provide for numerous additional advantages, as explained herein and as one skilled in the art will recognize.